Cranberry products and urinary tract infections in at-risk groups
What it found
In 23 trials in people, taking cranberry products cut the number of urinary tract infections in groups prone to them.
The authors say the finding should be read with caution.
What they found
Studies in people
Overall infection risk
Across the 23 trials, cranberry products reduced the number of people who got a urinary tract infection compared with placebo or control. The authors describe this as a 30% reduction in risk.
Women with repeated UTIs
In women who get urinary tract infections again and again, cranberry products lowered the number who got another infection. The authors report a 32% relative risk reduction in this group.
Children
In children, cranberry products lowered the number who got a urinary tract infection. The authors report a 45% relative risk reduction in this group.
People with catheters
In people using an indwelling catheter, cranberry products lowered the number who got a urinary tract infection. The authors report a 51% relative risk reduction in this group.
Juice versus capsules
People who used cranberry juice saw a bigger drop in infections than those who used cranberry capsules or tablets. The authors report a 35% relative risk reduction for juice compared with capsules or tablets.
Groups with no clear effect
Cranberry did not significantly lower infections in people with a neuropathic bladder, pregnant women, or older adults. The authors say the effect was not significant in these subgroups.
What the authors conclude
“In conclusion, our meta-analysis demonstrates that cranberry supplementation significantly reduced the risk of developing UTIs in susceptible populations.”
Also in their conclusions
- They conclude that cranberry supplementation significantly reduced the risk of developing urinary tract infections in susceptible populations.
- They say cranberry can be considered as adjuvant therapy for preventing urinary tract infections in susceptible populations.
- They advise that the conclusion should be interpreted with caution because of limitations in the included studies, and that further high-quality studies with appropriate large sample size are required.
How it was done
Guidelines have not reached a firm conclusion on whether cranberry helps prevent urinary tract infections, and the quality of evidence has been low. The authors wanted an up-to-date answer for people who get these infections often.
They pooled 23 randomised trials with 3,979 participants, comparing cranberry products with a placebo or control. The people studied included women with repeated infections, children, pregnant women, older adults, people with a catheter and people with a neuropathic bladder.
What it can’t tell you
- The trials used different cranberry products, doses and definitions of urinary tract infection, so the results cannot be pinned to one exact product or amount.
- Few of the included studies lasted longer than a year, so the long-term effects are not known.
- The review cannot show whether cranberry works in people who are not in the susceptible groups studied.
Who paid
- Conflicts
- The authors have declared that no competing interests exist.
- Authors work at
- Southeast University, P.R. China
The paper
- Title
- Consumption of cranberry as adjuvant therapy for urinary tract infections in susceptible populations: A systematic review and meta-analysis with trial sequential analysis
- Type
- Systematic review and meta-analysisThe authors follow a set, published method to find every relevant study, then combine the numbers from them into one result.
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Xia JY, Yang C, Xu DF, Xia H, Yang LG, Sun GJ (2021). Consumption of cranberry as adjuvant therapy for urinary tract infections in susceptible populations: A systematic review and meta-analysis with trial sequential analysis. PloS one. doi:10.1371/journal.pone.0256992Free full textPubMed 34473789DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error